1. Field of the Invention
The present invention relates to an imaging apparatus and a control method thereof.
2. Description of the Related Art
Conventionally, an imaging apparatus using a single-panel color image sensor generally applies the so-called development process to image information (RAW image) obtained by an image sensor, and performs compression encoding on the developed luminance signal and color difference signal, and records the encoded signals in a JPEG format in a recording medium. The development process includes, but is not limited to a demosaicing for performing color interpolation on each pixel to generate a signal composed of a luminance and a color difference, noise reduction on the signal, white balancing, optical distortion correction, and image adjustment.
Meanwhile, there are imaging apparatuses capable of recording RAW images (Japanese Patent Laid-Open No. 2011-244423). As compared with JPEG format or the like, a RAW image requires an enormous amount of data for recording, but is advantageous in that it allows flexible post editing, while minimizing deterioration in image quality.
Since the RAW image has been originally used only within imaging apparatuses, the manufacturers of the imaging apparatuses have their own proprietary formats, which are not compatible with one another. For this reason, in order to be able to check an image with a commonly used apparatus, the RAW image needs to be developed to generate an image in a general-purpose format such as JPEG. However, in recent years, the number of pixels of image sensors has increased, and along with this, the throughput necessary for the development process has been increased. Accordingly, a circuit for high-speed processing is required to perform the development process in real time in parallel with shooting, leading to an increase in the circuit scale and the power consumption.
On the other hand, it is conceivable to record only a RAW image and perform the development process when needed to reproduce the image. However, as described above, there is the problem that the RAW image is not versatile and thus cannot be developed by an apparatus of a different manufacturer, for example.